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Few pests elicit the negative response of ticks. Because of their persistent
blood-sucking behavior, they transmit several potentially debilitating and
Lyme disease, in particular, has attracted national attention and is now the
number one arthropod-borne disease in the United States.
Other tick-transmitted diseases include Rocky Mountain Spotted Fever, Erlichiosis
and Babesiosis. Ticks prefer to lie in woods, tall grass, weeds and brush. They
are seldom a problem in well-maintained lawns although edges of property
supporting tall weeds and brush can be a source of infestation.
Lyme disease is the most common arthropod-borne disease in the U.S. The deer
tick is responsible for lyme disease in the northeast and in the north central
states, and the black legged tick in the west. The disease most commonly occurs
during the summer months when ticks are most active; however, the symptoms of
chronic, untreated Lyme disease can occur at any time of the year. There are
three areas where risk of getting the disease is much greater than elsewhere. the
northeast states of Massachusetts, Connecticut, Rhode Island, New York, New
Jersey, and Pennsylvania; the north central states of Wisconsin and Minnesota;
and finally the Pacific Coast states of California and Oregon. A characteristic
rash or lesion develops a few days to a few weeks after the bite of an infected
tick. The rash generally looks like an expanding red ring with a clear center,
but it can vary from a blotchy appearance to red throughout. Sometimes there are
two or more lesions. Sometimes patients never get a rash, making diagnosis
difficult. At about this time, flu-like symptoms may appear along with headache,
stiff neck, fever, muscle aches, and/or general malaise. Some symptoms and signs
of Lyme disease may not appear until weeks, months, or years after a tick bite.
Arthritis is most likely to appear as brief bouts of pain and swelling, usually
in one or more large joints, especially the knees. Nervous system abnormalities
can include numbness, pain, Bell's palsy (paralysis of the facial muscles,
usually on one side), and meningitis (fever, stiff neck, and severe headache).
Less frequently, irregularities of the heart rhythm occur. In some persons the
rash never forms; in some, the first and only sign of Lyme disease is arthritis,
and in others, nervous system problems are the only evidence of Lyme disease.
Human ehrlichioses are two fairly recently identified tickborne diseases of man.
Human monocytic ehrlichiosis is transmitted primarily by the Lone Star tick.
Most cases have occurred in the southeast and south central U.S. Cases have also
been confirmed in Washington State and Massachusetts. Human granulocytic is
transmitted to humans by the deer tick. Most cases have occurred in the upper
Midwest (Minnesota and Wisconsin). A few additional cases were identified in New
York, Connecticut, Maryland, and California. Both diseases are clinically similar
to Lyme disease in their "flu-like" symptoms including fever, headache,
fatigue, and muscle pain. They differ from Lyme disease in their rapid onset of
these symptoms, especially elevated fever accompanied by very severe headache.
Human ehrlichioses also differ from Lyme disease in the absence of the
characteristic rash around the tick bite. Infection usually produces mild to
moderately severe illness but may occasionally be life threatening or even fatal.
The incubation period is usually one to three weeks after exposure to an infected
tick. However, not every exposure results in infection.
Babesiosis is transmitted to man by the deer tick. Cases of this disease have
been reported during spring, summer, and fall in coastal areas in the
northeastern United States, especially Nantucket Island off the Massachusetts
shore and on Long Island, New York. Cases have also been reported in Wisconsin,
California, and Georgia. Symptoms, if any, usually begin within one week of being
bitten. Most people who are infected have no apparent symptoms. For those that
do have symptoms, there is a gradual onset of not feeling well with loss of
appetite and fatigue. As the disease progresses fever, drenching sweats, muscle
aches and headache may be experienced. Some individuals a serious sometimes fatal
disease with hemolytic anemia., kidney failure, liver dysfunction and/or very low
blood pressure. Symptomatic babesiosis is seen most frequently in the elderly
and immuno-compromised individuals. Most of the fatal cases are seen in
patients who have had their spleen removed.
Rocky Mountain Spotted Fever occurs primarily along the southern Atlantic Coast
although cases also occur in the mid-west through the Rocky Mountain States and
on to the pacific coast. Most cases occur between April and September. Three
ticks commonly transmit the disease to man; the Rocky Mountain wood tick in the
west; the American dog tick in the east and in parts of the Pacific Coast; and
the lone star tick in parts of the Eastern U.S. and in Texas, Oklahoma, and
Arkansas. About 3 to 10 days after tick attachment, the disease starts with a
definite fever, often with chills, headache, or muscle aches. A rash usually
appears after 1-3 days of fever, usually on the wrists and ankles. At first the
rash resembles that of measles. Later the rash may spread to the rest of the body.
Because they are more likely to be exposed to ticks, children living in rural and
suburban areas and children attending youth camps are likely to become infected.
The disease is severe at all ages, but it is more severe in adults, especially the
Tickborne paralysis is a potentially fatal reaction to a paralyzing toxin
secreted in the saliva of a female tick during the late stages of feeding.
Vectors of this illness include the Rocky Mountain wood tick (Dermacentor
andersoni), the American dog tick (Dermacentor variabilis), the Lone Star tick
(Amblyomma americanum), Amblyomma maculatum, Ixodes scapularis (black-legged tick),
and Ixodes pacificus (western black-legged tick).
Signs and symptoms of this illness include: headache, vomiting, general feeling of
exhaustion and loss of motor function and reflexes. These symptoms are followed by a
paralysis that starts in the lower body and spreads to the rest of the body. The
paralysis can cause respiratory failure and death results in approximately 10% of
The illness is most commonly found in the Rocky Mountain and northwest regions of
the United States and western Canada.
Tickborne Relapsing Fever (TBRF) is a systemic disease in which periods of fever
lasting 2-9 days alternate with periods of no fever, which last for 2-4 days. These
relapses can vary from 1 to 10 or more. A rash may be present during the fever periods.
The average incubation period is eight (8) days; with a range of 5-15 days. The total
duration of the disease averages 13-16 days. Approximately 2% to 10% of untreated
cases can result in death.
TBRF is endemic throughout much of the western United States, with sporadic cases
occurring each summer and fall. The disease is caused by infection with the
spirochetes Borrelia hermsii or B. turicatae. The soft ticks of the genus
Ornithodoros, which transmit the illness, usually feed on rodents and frequently
infest rodent nesting material. The ticks are reclusive, usually feeding at night
for only 5-20 minutes. Their bites are painless and frequently go unnoticed.
Humans are incidental hosts when bitten by an infected tick. Cabins in wilderness
areas are attractive nesting sites for potentially infected rodents, particularly
when food is made available by cabin users. Most infections are acquired by
persons vacationing in mountain cabins where rodents have nested.
It is important to seek medical attention if you suspect you have been bitten by
a tick and especially if you are experiencing any of these symptoms of the above
mention diseases. Timely treatment is essential.
In some areas ticks saved in a sealed container can be submitted to the local
health department for identification.
The best way to avoid acquiring ticks and tick-borne diseases is through prevention.
- Avoid tick-infested areas, especially in spring and summer months.
- Stay on the center of trails and paths - don't brush against vegetation if you can avoid it.
- Wear long pant, and tuck in your pants legs. Better still, tape the area where pants and socks meet.
- Wear a hat and a long-sleeved shirt for extra protection.
- Wear light colored and tightly woven clothing to more easily see ticks.
- Use insect repellent. Products containing DEET can be used on either skin or clothing. Permethrin can be used only on clothing. Both are readily available.
- Frequently check yourself, children and pets for ticks. Ixodid ticks are about the size of a pinhead, therefore easily overlooked. Other ticks are larger, about the size of a pencil eraser or larger.
- Remove ticks from your skin immediately with tweezers by grasping the tick's head parts as close to your skin as possible. If mouthparts remain embedded in skin, contact your physician. Wash the bite area, apply antiseptic and cover with a band-aid. Ticks are slow feeders. Risk of infection is greatly reduced if they are removed within 24 hours.
- Where possible, keep grass and shrubs in your yard trimmed, and clear overgrown.
- Treating lawns is of little benefit since this is not a preferred habitat for ticks.
If you have any questions, please contact your nearest Regional Point of Contact,
park sanitarian or call WASO Public Health for more information.
Health Information, National Center for Infectious Diseases, Centers for Disease
Control and Prevention, Department of Health and Human Services.
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